Process of refining hydrocarbon oils



June 9 1931' LACHMAN. 1,809,170.v I Pnocnzssl oF REFINING HYDRocAnBoNOILS Filed May 8. 1929 Patented June 9, v1931 UNITED STATES 'PATENTOFFICE' ARTHUR LACHMAN, Fl BERKELEY, CALIFORNIA, .ASSIGrN'OR T0RICEFIELD OIL COM- WARE Application led May 8,

This invention relates to a process of purifying and refininghyd-rocarbon oils obtained by distillation or cracking vof mineral oils,such as lubricating oils, lamp oils, gasoline stocks or distillatesderived from oil shale. This application is a continuation in part of-my pending application SerialA No. 200,589, filed June 22, 1927 formethod of relining mineral oils, which consists of a similar method orprocess for purifying and rening mineral oil products with a Watersolution of zinc chloride.

The process of refining hydrocarbon oils, as described in thisapplication, is applicable to all mineral oil products derived bydistillation or cracking operations, such as lubricating oils, lamp oilstocks, gasoline stocks distillates derived from oil shale, etc., an isparticularly adaptable to gasoline stocks 2 obtained by cracking higherboiling hydrocarbon oils. For the purpose of simplifying thedescription, reference will be made 'to gasoline only.

Crude gasoline stocks obtained by distilling. or cracking petroleum oilsconsist of a mixture of saturated and unsaturated hydrocarbons togetherwith sulphur compounds, nitrogen bases and other substancesl of an,nundeined nature.

s are readily oxidizable at ordinary temperatures and are usuallyresponsible for the change of color which takes place when renedgasoline is stored. These oxidizable substances are removed Withdiiiculty when 5 gasoline stocks are treated by the methods known incommon use.

ln order to show the nature of my invention, it is desirable to describethe method now in common use in oil reneries, and.

(m particularly that step of refining gasoline stocks which consists indeodorizing and stabilizing the same. Crude gasoline stocks obtained bydistillation of crude petroleum oil or by cracking a higher boilingpetroleum oil, are customarily treated With approximately from l percent to as high as 8 per cent by Weight sulphuric acid, the quantity ofsulphuric acid depending upon the nature of the gasoline stock to betreated and the product desired. This acid treatment usual- These lattersubstances wiPANY or CALIFORNIA, or Los ANGELES, cAmronNrA, ACORPORATION on DELA- PRooEss or REFINING HYDRocARBoN OILS ya 'I 1929.Serial No. 361,513.

ly consists in commingling the gasoline Stock With the required amountof sulphuric acid .necessary to obtain the desired extraction, either bythe Well-known batch Aor continuous treatment, after Which the productsof the acid reaction are permitted to settleiand then Withdraw from thetreated gasoline stock. The acid treated gasoline stock is thenneutralized by Washing with a Water solution of an alkali and nally withWater. This treatment removes most of the impurities, but subsequenttreatments areusually necessary to deodorize and remove or convertcorrosive Sulphur compounds into noncorrosive bodies. For this purpose,a Water solution of sodium plumbite or sodium hypochlorite is usuallyemployed to render the gasoline sweet to the doctor test.

The general objections to a treatment of this character are as follows:

(l) Gasoline purified by this method frequently becomes discolored whenstored for a period of time;

(2) considerable quantities; of sulphuric acid are required, which aredifficult to recover; K A

(3) as high as 10 per cent of the valuable stable unsaturatedhydrocarbons contained in the gasoline stock may be lost; and

(4:) the treatment must frequently be followed by a deodorizing orsweetening process, such as that heretofore described.

Now, l have discovered that the sulphuric acid normally used to treatcrude gasoline stocks may be reduced to a high extent, and in many casesmay be entirely eliminated by the employment of a water solution ofcertain metallic salts, or mixtures of the same, which may be zinc,copper, cadmium, mercury, iron, chromium, manganese, aluminum, nickel orcobalt Water soluble salts, Such as the chloride, bromide, iodide,sulphate, nitrate, and also any of the Water soluble salts ofthe abovenamed metals of organic acids, such as the sulphonic acids of benzol,toluol and xylol, or the sulphonic acids derived from the treatment ofpetroleum oils with sulphuric acid.

The process described briefly consists in passing the hydrocarbon oilproduct such as gasoline lstock while in a vapor state, through or incontact with a hot concentrated water solution of any of the aforesaidyao metallic salts or mixtures thereof. The gasoline stock so treated isusually pure enough for immediate use, although it sometimes may containsmall'amounts of hydrogen sulphide, which may be removed by washing withan alkaline solution of sodium or calcium hydroxide, or the carbonatesof sodium or potassium.

The hydrocarbon oil stock to be treated by my invention may or may nothave had a preliminary treatment with sulphuric acid, or other agents topartly purify the same, or may be first partly purified by my inventionand the purifications completed by methods known in the art, such astreatment with caustic alkali, sulphuric acid, etc. lin case ofgasolinestocks produced by cracking high sulphur bearing, crude petroleum oilsor residuums, it may be advantageous toI treat such gasoline Stocks withsmall amounts of sulphuric acid before the treatment with a concentratedwater solution of any of the afore-stated metallic salts, which may alsobe followed by treatment with an alkaline water solution of sodium,potassium or calcium hydroxide, or the carbonates of sodium orpotassium.

Although a solution of less concentratio may be employed which may rangefrom 50 or less to approximately 85 per cent, the

strength of the water solution of the metallic salt or mixture of saltsemployed is preferably a substantially concentrated solution, and thetemperature employed for the treatment is approximately 300 to 400degrees iF.,

which normally fluctuates, depending upon the vaporizing temperature ofthe oil under treatment.

With the foregoing preliminary ex lanation, the preferred embodiment ofmy invention will now be more fully explained by reference to theaccompanying drawing which is a diagrammatic view of one formofapparatus which may be employed for carrying out the objects of thepresent invention.

Referring to the drawing, 2 indicates a pipe leading to a source ofcrude gasoline vapors not shown, such as a fractionating tower employedto separate the lower boiling oils from the'higher boiling4 oils. Bindicates a tower of suitable height and diameter filled with resistantorcontact material, such as fire brick, spiral tile or the like,indicated at 3, which forms numerous tortuous passages through thetower, although it is to be. understood that the well-known bubble capcontact tower may be employed. Disposed above the tower or adjacent tothe same, is a tank l2 containing a substantially concentrated watersolution of a metallic salt or mixtures of the same, as heretoforeenumerated, having a concentration of from asoaivo 50 per cent or lessto as high as approximately 85 per cent. This tank is connected to thetop of the lower by means of a pipe 4 having a regulating valve 5. Thispipe terminates over a spreader plate 6 and this plate evenlydistributes the water solution of the metallic salt or salts when thevalve 5 is opened, over the brick work or contact material.' The watersolution of the metallic salt or salts flows downward through thiscontact material andv may finally be discharged through the bottom by apipe 7, after which it is treated for recovery. 'lhe tower B is alsoprovided with a steam or water inlet pipe 8, which intermittently orcontinuously supplies a predetermined amount of water or steam to thetower. The hot gasoline vapors from the' pipe 2 enter the lower end ofthe tower B at a point 9. rlihey oil vapors pass up through the numerouscontact passages in the brick work and thereby come into intimatecontact with the said water solution of metallic salt Aor salts flowingover the same. temperatures may be employed, both the Water solution ofmetallic salt or salts and oil vapors are generally maintained at atemperature of approximately 300 to 400 degrees F., and the oil vaporsare discharged at the upper end of the tower through a pipe 10 which isconnected with a condenser- 11 of suitable construction. The gasolinevapors passing through the contact tower B at the temperature s ecified,vaporize a certain amount of water rom the water solution of metallicsalts and the purpose of the steam or water inlet pipe 8 is that ofcontinuously maintaining the solution ata certain water content so as tomaintain the necessary Huidity which is essential for good contactbetween the. rising gasoline vapor and the down-flowing water solutionof metallic salt or salts. the water solution of metallic salt or saltsis maintained at its predetermined -limits of concentration by acontinuous introduction of water or water vapor. Otherwise solidmetallic salt or salts and solid sludge impurities may plug the passagesthrough which the gasoline vapors are being conducted.

While not always necessary, it is beneficial that the water solution ofmetallic salt or salts contain hydroxides or oxides of' any of themetals, or mixtures thereof, heretofore enumerated, before beingintroduced into the system. This may be accomplished by agitating theWater solution of the metallic salt or salts with any of the hydroxidesor oxides of any of the enumerated metals. The optimum amount of themetal oxide or hydroxide ranges from about 1/2 of l per cent to 3 percent by weight of the water solution of metallic salt or salts. tion,when the oxides or hydroxides of any Although other Preferably theconcentration of of the aforementioned .metals or mixtures thereof aresoluble in substantial amounts in the salt or salts solution at' thetemperatures and pressures employed, it is no doubt that the beneficialaction will be enhanced but even if no vsubstantial solubility exists,useful effects can be obtained if the oxides and hydroxides aresuspended in the salt or salts solution.

The reaction tower B is kept full of the Water solution of the metallicsalt or salts containing metallic hydroxides or oxides suchV as zinchydroxide, and. a fresh' supply of approximately 15 pounds of the saidsolution is admitted for each barrel .of gasoline stock under treatmentand a corresponding amount of the spent solution is Withdrawn at thesame time.

v The amount of Water vapor required to replace the vaporized water fromthe Water solution of metallic salt or salts varies Within Wide limits,depending upon the concentration of the solution employed, thetemperature at which the operation is carried out and the nature andamount of'inert gases which may accompany the gasolinev vapor beingtreated. Approximately 50 to 100 pounds of Water or Water vapor willusually be suficient` for each barrel of gasoline stock treated. By thistreatment the major portion of the impurities contained by the gasolinestock Ais removed and carried out With the Water solution of metallicsalt or saltsv as a sludge and the purified gasoline vapors,

when condensed, are suitable for use as a refined gasoline stock of highpurity.

While the process herein described is well.

ladapted for carrying out the objects of the claims.

What I claim is:

1. A process of refining mineral oils, comprising, vaporizing a mineraloil, contacting the vaporized oil with a water solution of a zinc saltmaintained in solution and then condensing purified oil vapor separatedfrom products of reaction and treating agent.

2. A process of refinlng mineral oils, c'olnprising, vaporizing amineral oil by theiapplication of heat, contacting the heated vaporizedmineral oil with a substantially concentrated solution of a zinc saltmaintained in solution and then condensing purified oil vapor separatedfrom products of reaction and treatin agent.

3. A process of re ning mineral oils, comprising, vaporizing a mineraloil, contacting the vaporized mineral oil with a Water solution of amixture of zinc salts maintained-in solution and then condensingpurified oil vapor separated from products of reaction and ltreatinagent.

4. A process of re Yning mineral oils, comprising, vaporizing a mineraloil by the application of heat, contacting the heated vaporized mineraloil With a heated Water solution of a zinc salt maintained in solutionand then condensing purified oil vapor separated from products ofreaction and treating agent.

5. A lprocess of refining mineral oils, comprising, vaporizing a mineraloil by the application of heat, contacting the heated vaporized mineraloil with a heated Water solution of a zinc salt maintained in solutionand heated to a temperature of not less than the vaporizing temperatureof the vaporized mineral oil under treatment, and then condensingpurified oil vapor separated from products of reaction and treatingagent.

6. A process of refining mineral oils, comprising, heating a mineral oilto form a vapor at vtemperatures of approximately 300 to 400 `degreesF., contacting the heated vapors with a Water solution of a zinc saltmaintained in solution at a substantially similar temperature and thencondensing purified oil vapor separated from products of reaction andtreating agent.

7. A process of refining mineral oils, comprising, heating a lmineraloil to form a vapor at temperatures of approximately 300 to 400 degreesF., passing the heated vapors through or in contact with a Watersolution of zinc salts maintained in solution at a substantially similartemperature and having a concentration of approximately 50-85% and.v

then condensing purified oil vapor separated from products of reactionand treating agent.

8. A process of refining mineral oils, co1n. prising, heating a mineralo1l toform avapor, contacting the heated vapor with a water solution ofzinc salts maintained in a fluid condition and containin zinc hydroxide,and then condensing purified oil vapor separated from products ofreaction and treating agent.

9. A process of refining mineral oils, comprising, heating a mineral oilto form a vapor, passing the heated vapor through and in contact with aWater solution of zinc salts, maintaining the solution in a fluidcondition bythe addition of Water and condensing the vapor after passingthrough the solution.

10. A process of refining mineral oils, comprising, commingling thevapors of a mineral .oil With a water solution of a zinc salt maintainedin a fluid condition and then condensing purified oil vapor separatedfrom products ofreaction and treating agent.

11. A process of refining mineral oils, comprising, heating a-mineraloil to form. a vapor, passing the heated vapors through and in contactWith a Water solution of a zinc salt containing zinc hydroxide,maintaining the solution in a fluid condition by the addition of Waterduring contact of the vapors With the treating solution andcondensing'the vapor after passing through the solution.

12. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, passing the heated vapor through and in contactwith a Water solution of zinc salts containing from 1/2 of 1 per cent to3 peil cent by Weight of Zinc hydroxide and zinc oxide, maintaining thesolution in a Huid condition by addition of Water during contact of thevapors With the treating solution and condensing the Vapor after passingthrough the solution.

13. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, passing the heated vapor through and in contactWith a Water solution of zinc salts, maintaining the concentration ofthe solution within predetermined limits by the addition of Water andcondensing the vapors after passing through the solution.

14.' A process of refining mineral oils, comprising, heating a mineraloil to form a vapor at temperatures of approximately 300 Ato 400 degreesF., passing the heated vapor tion of a zinc salt, intermittentlyintroduc-lv ing water into the solution of zinc salt to maintain theaqueous solution and continu'- ously condensing vapors of the purifiedmincral oil separated from the products of reaction and solution of zincsalt.

16. A process of refining mineral oils,

v comprising, heating a mineral oil to form a vapor, passing the vaporthrough and in contact with a water solution of zinc salts containingzinc hydroxide, intermittently introducing Water into the solution ofzinc salts to maintainthe aqueous solution containing zinc hydroxide andcontinuously condensing the vapors of the vpurified mineral oilseparated from the products of reaction and solition ofzinc salts'containing zinc hydrox- 1 e.

17. A process of refining mineral oils,

comprising, heating a mineral oil to form a 4 1n testimony whereof ll axmy signature.

ARTHUR LACHMAN.

through and in contact with a water solution

